Carboniferous Conodont Biostratigraphy of Three Cores in Eastern Kansas
This study involves the species-level identification and biostratigraphy of conodont assemblages in the early middle Pennsylvanian (Atokan Stage) of eastern Kansas. The study also provides insight into the middle and upper Mississippian. Several of the cores contained Meramecian and Chesterian conodonts faunal assemblages. There is little Atokan rock preserved in the midcontinent region overall (Barrick et al, 2004. The identification and subsequent correlation of Atokan strata will improve the knowledge of this stage. This series was sampled in eastern Kansas (both outcrop and core), and in northeastern Oklahoma (outcrop only). The results from outcrop samples provided uniformly poor conodont recoveries, typical of the Cherokee. The results from the core samples were significantly better in terms of conodont recovery, but the faunas were unexpectedly diachronous: Atokan from one core, Chesterian from another, and Meramecian from the third. These results do not contradict the work done by Peppers and Brady (2007), who assigned some of the rocks in southeastern Kansas to the Atokan Stage. This study identifies potential coal miscorrelations that suggest Atokan rock might be present in Kansas and Oklahoma. Based on the conodont assemblages recovered from the subsurface, Atokan strata lies significantly higher in previously described cores than initially thought---up to 75 feet (22.86m) in the area surrounding the Norma Morris # 5 -- 1 core in Neosho County. Because the subsurface results of this study were from such non-correlative intervals, further study is needed to confirm previous interstate correlations of Atokan strata in the subsurface of eastern Kansas.